Two same-sex couples in Texas filed a federal lawsuit this week challenging the state's constitutional ban on same-sex marriage that was overwhelmingly approved by voters in 2005. The couples argue that the ban unconstitutionally prevents them from enjoying the benefits of married couples, while the state's Attorney General Greg Abbott has vowed to vigorously defend the ban.

Lawyers for the couples said in court documents filed this week in the U.S. District Court in San Antonio that their clients are being unconstitutionally discriminated against by not being allowed to marry in the state, where in 2005, nearly 75 percent of voters approved a constitutional amendment defining marriage as being between one man and one woman. The lawsuit specifically argues that the June ruling by the U.S. Supreme Court that overturned a key provision of the Defense of Marriage Act conflicts with state-to-state bans on same-sex marriage.

The two couples, Cleopatra De Leon and Nicole Dimetman of Austin and Victor Holmes and Mark Phariss of Plano, are seeking an injunction to halt the state law banning same-sex marriage. "There is no rational basis, much less a compelling government purpose, for Texas to deny plaintiffs the same right to marry enjoyed by the majority of society," attorney Barry Chasnoff, who is representing that plaintiffs, said in a statement to the Associated Press. Currently, 16 states in the U.S. have legalized same-sex marriage, the most recent ones being Illinois and Hawaii.

Lauren Bean, a spokeswoman for Abbott, said the attorney general is prepared to defend the voter-approved ban on same-sex marriage, arguing that the Supreme Court was clear to ensure in its ruling that individual states would have the authority to determine same-sex marriage legalization. "The U.S. Supreme Court was clear that states have independent authority to establish their marriage laws. Texans adopted a constitutional amendment defining marriage. We will defend that amendment."

Jonathan Saenz, president of the conservative group Texas Values, told WOAI radio station that the "Texas law is absolutely clear that same sex marriage is illegal."

"The only way that homosexual advocates win this case is if federal judges abuse their power, legislature from the bench and violate nearly every principle of law and policy in our state and country."

Saenz added that he believes Abbott will "defend our law and our Constitutional vigorously." Abbott is currently a Republican candidate for the upcoming governor's race next year.

A federal judge could hear arguments regarding this recent lawsuit as early as January. Earlier this year, Texas' National Guard commander Maj. Gen. John Nichols ordered all of the state's military forces to not process any applications from same-sex couples seeking military benefits. The Guard initially argued that it was a state agency and therefore could not process same-sex couples' requests due to the state ban on same-sex marriage. Then, on Tuesday, the Guard announced that it will in fact accept applications from same-sex couples after the Department of Defense approved a new procedure that allows applications to be processed by federal officials, thus removing the conflict with state law.